An endarterectomy or atherectomy catheter is a device that is inserted in an artery to remove plaque from the walls of the arteries. This helps to decrease the risk of heart attacks. In medical terms, an endarterectomy catheter is a device used for the mechanical recannalization of occluded arteries. Occlusions of the vascular lumen may result from atherosclerotic lesions in human coronary arteries resulting in unstable angina and eventual myocardial infarction.
Several atherectomy catheters have been developed but all are relatively complicated and expensive devices.
Simpson, U.S. Pat. No. 4,781,186, describes a double chambered catheter with a rotating cutting blade. The distal end of the catheter consists of a solid cylindrical blade in a longitudinal housing with a longitudinal window over a third of its circumference. The window is on one side and a balloon is on the other side of the catheter. The housing and the rotating blade are made of stainless steel. The blade is attached to a torque cable in one of the catheter chambers. This chamber is also used to inject fluid or contrast media into the artery. The other chamber is used for balloon inflation. A short terminal fixed guide wire assists in positioning the window towards the atherosclerotic lesion. The cutting blade is then activated by a hand held motor at 2,000rpm and the blade is rotated against the lesion. Excised plaque is trapped inside the catheter. A separate mechanism is used for balloon inflation. Other related patents for the Simpson atherectomy catheter are European application 352,872, U.S. Pat. Nos. 4,771,774; 4,669,649; and 4,616,648.
Auth, U.S. Pat. No. 4,445,509 describes a catheter having a rotating abrasive burr that can be advanced over a movable guide wire. The burr rotates at 150,000 rpm or higher and is driven by a compressed air turbine. The turbine also pumps a saline solution to cool the fast moving parts.
Theratek International of Miami, Fla., provides a single lumen flexible polyurethane catheter (also called the Kensey atherectomy catheter), having a rotating metallic cam at the distal end which is driven at 100,000 rpm to emulsify the targeted lesion.
Ultramed, Inc. of San Diego, Calif., provides a transluminal extraction endarterectomy catheter having a rotating steel cutting blade. The blade rotates at high speed, 750 rpm, to excise the targeted lesion. A vacuum is used to retrieve the debris from the lesion.